move test case iteration to caller

To make the test case logic more obvious

agent/config/runtime_test.go

@@ -42,13 +42,18 @@ type testCase struct {
 	patch func(rt *RuntimeConfig) // expected
 	err   string                  // expectedErr
 	warns []string                // expectedWarnings
-
 	opts  LoadOpts
-
 	json  []string
 	hcl   []string
 }
 
+func (tc testCase) source(format string) []string {
+	if format == "hcl" {
+		return tc.hcl
+	}
+	return tc.json
+}
+
 // TestConfigFlagsAndEdgecases tests the command line flags and
 // edgecases for the config parsing. It provides a test structure which
 // checks for warnings on deprecated fields and flags.  These tests
@@ -4846,63 +4851,41 @@ func TestLoad_IntegrationWithFlags(t *testing.T) {
 		},
 	}
 
-	testConfig(t, tests, dataDir)
+	for _, tc := range tests {
+		if len(tc.json) == 0 && len(tc.hcl) == 0 {
+			testConfig(t, tc, "", dataDir)
+			continue
 		}
 
-func testConfig(t *testing.T, tests []testCase, dataDir string) {
-	for _, tt := range tests {
-		for pass, format := range []string{"json", "hcl"} {
+		for _, format := range []string{"json", "hcl"} {
+			testConfig(t, tc, format, dataDir)
+		}
+	}
+}
+
+func testConfig(t *testing.T, tc testCase, format string, dataDir string) {
+	t.Run(fmt.Sprintf("%v_%v", tc.desc, format), func(t *testing.T) {
 		// clean data dir before every test
 		os.RemoveAll(dataDir)
 		os.MkdirAll(dataDir, 0755)
 
-			// when we test only flags then there are no JSON or HCL
-			// sources and we need to make only one pass over the
-			// tests.
-			flagsOnly := len(tt.json) == 0 && len(tt.hcl) == 0
-			if flagsOnly && pass > 0 {
-				continue
+		if tc.pre != nil {
+			tc.pre()
 		}
 
-			// json and hcl sources need to be in sync
-			// to make sure we're generating the same config
-			if len(tt.json) != len(tt.hcl) {
-				t.Fatal(tt.desc, ": JSON and HCL test case out of sync")
-			}
-
-			// select the source
-			srcs := tt.json
-			if format == "hcl" {
-				srcs = tt.hcl
-			}
-
-			// build the description
-			var desc []string
-			if !flagsOnly {
-				desc = append(desc, format)
-			}
-			if tt.desc != "" {
-				desc = append(desc, tt.desc)
-			}
-
-			t.Run(strings.Join(desc, ":"), func(t *testing.T) {
-				opts := tt.opts
+		opts := tc.opts
 		fs := flag.NewFlagSet("", flag.ContinueOnError)
 		AddFlags(fs, &opts)
-				require.NoError(t, fs.Parse(tt.args))
+		require.NoError(t, fs.Parse(tc.args))
 		require.Len(t, fs.Args(), 0)
 
-				if tt.pre != nil {
-					tt.pre()
-				}
-
 		// Then create a builder with the flags.
 		patchLoadOptsShims(&opts)
 		b, err := newBuilder(opts)
 		require.NoError(t, err)
 
 		// read the source fragments
-				for i, data := range srcs {
+		for i, data := range tc.source(format) {
 			b.Sources = append(b.Sources, FileSource{
 				Name:   fmt.Sprintf("src-%d.%s", i, format),
 				Format: format,
@@ -4910,19 +4893,20 @@ func testConfig(t *testing.T, tests []testCase, dataDir string) {
 			})
 		}
 
+		// build/merge the config fragments
 		actual, err := b.BuildAndValidate()
 		switch {
-				case err == nil && tt.err != "":
-					t.Fatalf("got nil want error to contain %q", tt.err)
-				case err != nil && tt.err == "":
+		case err == nil && tc.err != "":
+			t.Fatalf("got nil want error to contain %q", tc.err)
+		case err != nil && tc.err == "":
 			t.Fatalf("got error %s want nil", err)
-				case err != nil && tt.err != "" && !strings.Contains(err.Error(), tt.err):
-					t.Fatalf("error %q does not contain %q", err.Error(), tt.err)
+		case err != nil && tc.err != "" && !strings.Contains(err.Error(), tc.err):
+			t.Fatalf("error %q does not contain %q", err.Error(), tc.err)
 		}
-				if tt.err != "" {
+		if tc.err != "" {
 			return
 		}
-				require.Equal(t, tt.warns, b.Warnings, "warnings")
+		require.Equal(t, tc.warns, b.Warnings, "warnings")
 
 		// build a default configuration, then patch the fields we expect to change
 		// and compare it with the generated configuration. Since the expected
@@ -4934,8 +4918,8 @@ func testConfig(t *testing.T, tests []testCase, dataDir string) {
 
 		expected, err := x.Build()
 		require.NoError(t, err)
-				if tt.patch != nil {
-					tt.patch(&expected)
+		if tc.patch != nil {
+			tc.patch(&expected)
 		}
 
 		// both DataDir fields should always be the same, so test for the
@@ -4947,8 +4931,6 @@ func testConfig(t *testing.T, tests []testCase, dataDir string) {
 		assertDeepEqual(t, expected, actual, cmpopts.EquateEmpty())
 	})
 }
-	}
-}
 
 func assertDeepEqual(t *testing.T, x, y interface{}, opts ...cmp.Option) {
 	t.Helper()

agent/config/segment_oss_test.go

@@ -50,5 +50,9 @@ func TestSegments(t *testing.T) {
 		},
 	}
 
-	testConfig(t, tests, dataDir)
+	for _, tt := range tests {
+		for _, format := range []string{"json", "hcl"} {
+			testConfig(t, tt, format, dataDir)
+		}
+	}
 }